有3盏电灯连接于某电源上,如图所示.电源电压U不超过各盏电灯的额定电压.当电键S1和S2断开时,电灯L1最亮,L2次之,L3最暗,如果电键S1和S2闭合时,那么( )
A:L1最亮,L2次之,L3最暗
B:L2最亮,L3次之,L1最暗
C:L3最亮,L2次之,L1最暗
D:L3最亮,L1次之,L2最暗
小明家周末中午要举行家庭聚餐,妈妈早早就购买了大量食材,用以制作菜肴.
A、质子数 B、电子数 C、化学性质 D、____.
1.What are your best ____(祝愿)?
2.Their ____ (工作) are standing and watching at the door.
3.My friends are coming ____(不久).
4.He____ (听) to the teachers carefully in class.
5.My friend ____(写信) to me three times a month.